Pressurized Metered Dose Inhaler (MDI) canisters, which have been used since 1956, ordinarily are sold with a dispenser or so-called “boot” that includes an actuator, a nozzle, and a mouthpiece. The user can self-administer the MDI medicament using the boot alone; however, the user must place the mouthpiece of the boot in or near his/her mouth and inhale at essentially the same time the MDI canister is actuated. Some users, like young children and the elderly, find it difficult to coordinate their inhalation with the actuation of the MDI, and even if the user is able to coordinate their inhalation with MDI inhalation, a lot of medicament is deposited into the oropharynx, leading to undesirable side-effects, such as hoarseness or thrush when using corticosteroids.
At first, “Spacers” were created to address the undesirable oropharyngeal deposition; however, these devices do not address the need for coordinated breathing technique. Medical device manufacturers have since created valved holding chambers (VHCs) to address both issues. To combat oropharyngeal deposition, VHCs (like spacers) have a chamber that holds the aerosol plume. This chamber lets the aerosol plume decelerate giving medicament particles the volume needed to aerosolize, and it allows particles that would normally impact on the user's oropharynx to deposit on the inside of the chamber instead. To help alleviate any issues with the synchronization of a user's breath with MDI actuation, VHCs also employ a valving system that permits the user's inhalation to draw the medicament from the chamber but re-directs the user's exhalation to be vented out of the mouthpiece of the VHC such that the remaining aerosolized medicament inside the chamber is not blown backwards out of the chamber. This allows patients who can't synchronize their inhalation with MDI actuation to get a significant dose of medicament. It also allows the patient to continue breathing through the VHC throughout the treatment, as the presence of the exhalation valve means there is no need to remove the VHC from the patient's mouth during exhalation. Ultimately, the patient can take in the full dose, while breathing as normally as possible, over multiple breaths if necessary. These devices have now become the recommended as the best-practice accessory to an MDI for patients of all ages.
Many commercially available VHCs, like the Aerochamber Plus® Z-Stat® device available from Monaghan Medical Corporation, and Optichamber® Diamond device available from Philips Respironics, are made of rigid plastic and are substantially cylindrical in shape with a diameter of a couple inches and a length of roughly half a foot, which presents problems to users that need to carry MDI canisters with them all day in case of an emergency asthma attack. Also, in facilities that store large numbers of holding chambers, like hospitals or spirometry testing facilities, the cylindrical shape of most VHCs means that the storage of many VHCs takes up a significant amount of space. Some VHC manufacturers have identified these issues and have partially addressed them by creating collapsible cylindrical VHCs. Many of these collapsible VHCs, however, don't offer a significant advantage to a non-collapsible chamber. For example, the BreatheRite™ collapsible device available from Medline Industries, Inc., shortens the length of the device by a couple inches when collapsed, but the device is still a rigid cylinder with the same diameter. The cylindrical shape still means that the device can't fit comfortably in a user's pocket, as well as meaning that storing large quantities of these devices would still take large amounts of space. The Thayer Medical LiteAire® spacer device collapses to a substantially flat configuration and the dimensions of the VHC allow the device to be carried unobtrusively in a shirt pocket or purse. Also, many LiteAire® spacer devices can be stored in a relatively small area because the packaged devices can be stacked flat on top of each other with very little empty space between devices, which is not possible with cylindrically shaped devices like the BreatheRite™ collapsible device.
Conventional VHCs, like the Aerochamber Plus® Z-Stat® device and Optichamber® Diamond device, cost in the range of $10-20. Some medical applications, like spirometry testing, only require a VHC to be used during a brief testing period by a patient, and this price offers a barrier to the use of a VHC in these settings. While lower cost plastic VHCs have recently been introduced to the market, the recent awareness of the need for environmental sustainability identified another problem with the rigid cylindrical plastic solution. Plastic taxes the environment when disposed of with the frequency required in higher-usage clinical environments like spirometry testing facilities. The LiteAire® offers a solution to this problem as well, with 98% of the device being made from paperboard, the environmental impact upon disposal of the device is substantially reduced.
Another benefit of the LiteAire®'s collapsible device construction is that the device is made of a paperboard which is inherently an antistatic material. The fact that the traditional plastic construction of other VHCs creates a large amount of medicament deposition due to static build up on the inside surface of the VHC has been established by multiple sources, including some patents. Multiple patents have been filed for VHCs or spacers made from antistatic materials. For example, U.S. Pat. Nos. 6,435,176 and 7,360,537, which describe devices made from metal and antistatic plastic, respectively, seek to address this problem. These patents offer solutions to electrostatic deposition but run into some of the same rigidity, cost, and disposal problems mentioned above; and they remain bulky and/or expensive. The LiteAire® collapsible device is able to reduce electrostatic deposition as well as being inexpensive, easily portable and environmentally friendly.
While the current LiteAire® collapsible device offers an inexpensive, disposable, collapsible, and antistatic VHC, the current LiteAire® collapsible device employs plastic valves, which creates certain manufacturing challenges. The valves being a different material than paperboard, require a special form of adhesion. Adhesion could come in the form of solvent bonding, heat bonding, pressure bonding, vibration bonding or an actual adhesive, but regardless of the type of adhesion used, related extra steps and expenses in the manufacturing process are required. The replacement of separate plastic valves with valves made from the same sheet material as the rest of the device simplifies not only the manufacturing of the device, but also simplifies the selection of materials and bonding methods available for manufacturing, considering that bonding a material to itself requires less considerations than bonding two potentially dissimilar materials.
In addition to potential time and expense improvements made to the LiteAire® collapsible device manufacturing process, the replacement of the plastic valves with paperboard means that the disposal of the device in an ecologically friendly way, becomes much faster. This means that the replacement of the plastic valves with valves made of the same paperboard material as the body allows the new LiteAire® collapsible device to be made with 100% renewable resources.
The present application addresses these potential variants in the LiteAire® collapsible device design. These variants would continue to provide the same advantages that the current LiteAire® collapsible device already offers over the prior art discussed above and adds additional advantages.